645425633 has 2 divisors, whose sum is σ = 645425634. Its totient is φ = 645425632.

The previous prime is 645425629. The next prime is 645425639. The reversal of 645425633 is 336524546.

It is a happy number.

645425633 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 555403489 + 90022144 = 23567^2 + 9488^2 .

It is a cyclic number.

It is not a de Polignac number, because 645425633 - 2² = 645425629 is a prime.

It is a super-3 number, since 3×645425633³ (a number of 27 digits) contains 333 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (645425639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322712816 + 322712817.

It is an arithmetic number, because the mean of its divisors is an integer number (322712817).

Almost surely, 2^645425633 is an apocalyptic number.

It is an amenable number.

645425633 is a deficient number, since it is larger than the sum of its proper divisors (1).

645425633 is an equidigital number, since it uses as much as digits as its factorization.

645425633 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 259200, while the sum is 38.

The square root of 645425633 is about 25405.2284579376. The cubic root of 645425633 is about 864.2022707619.

The spelling of 645425633 in words is "six hundred forty-five million, four hundred twenty-five thousand, six hundred thirty-three".